LEDs are semiconductor photonic devices that emit light when a voltage is applied. LEDs have increasingly gained popularity due to favorable characteristics such as small device size, long lifetime, efficient energy consumption, and good durability and reliability. In recent years, LEDs have been deployed in various applications, including indicators, light sensors, traffic lights, broadband data transmission, back light unit for LCD displays, and other suitable illumination apparatuses. For example, LEDs are often used in illumination apparatuses provided to replace conventional incandescent light bulbs, such as those used in a typical lamp.
To configure the color of the light output from an LED, a photoconversion material such as phosphor may be utilized to change the light output from one color to another. However, conventional methods and techniques of applying photoconversion materials to LEDs suffer from drawbacks such as low throughput and high cost.
Therefore, although existing methods of applying photoconversion materials to LEDs have been generally adequate for their intended purposes, they have not been entirely satisfactory in every aspect. A cheaper and more efficient way of applying photoconversion materials to LEDs continues to be sought.